Resharpen Dull Drill Bits - Commercial quality drill bit sharpener designed for most types of twist drill and masonry bits from 3/32in. to 1/2in. in dia. in about 60 seconds. Sharpen at standard 118 degree or high-performance 135 degree, or high performance self centering split point bits. Can also convert standard bits to a different angle or split point. Depth gauge and drill holder guide the drill for perfect results. Use the optional 3/4in. adapter to extend sharpening coverage to include sizes over 1/2in. to 3/4in.. Replaceable diamond sharpening wheel sharpens hundreds of bits before needing replacement.